Tri-pod portable fan

ABSTRACT

An air blower including a rear housing defining a plurality of air inlet openings, a front housing having an annular peripheral portion secured to the rear housing, a central support portion within the peripheral portion, a grillwork portion extending between the peripheral portion and the support portion, and a fan assembly secured to the central portion and projecting toward the rear housing. The grillwork portion includes a plurality of vanes each of which is arcuately curved in shape and each of which is connected between the central support portion and the annular peripheral portion independently of the other.

This is a continuation of application Ser. No. 07/726,676, filed Jul. 8,1991, U.S. Pat. No. 5,304,040.

BACKGROUND OF THE INVENTION

This invention relates generally to a portable electrical fan and, moreparticularly, to a versatile, easily manufactured, and low cost portableelectrical fan.

Portable electrical fans are utilized to create air flow and therebyenhance environmental conditions. To optimize the flow patterns producedthereby, many portable fans are provided with supports that permitselective orientation of a fan member on a supporting pedestal. Althoughvarious types of fan supports have been proposed, prior supportmechanisms suffer from a number of individual and collectivedisadvantages such as high cost, cumbersome adjustment requirements,excessive size, insufficient orientation adjustment capability, etc.

The object of this invention, therefore, is to provide an improvedportable electrical fan that is inexpensive, easily assembled, and canbe easily transported to a position and adjusted to provide a desiredair flow orientation.

SUMMARY OF THE INVENTION

The invention is an air blower including a rear housing defining aplurality of air inlet openings; a front housing having an annularperipheral portion secured to the rear housing, a central supportportion within the peripheral portion and including a rear surfacefacing the rear housing and an oppositely directed front surface, and agrillwork portion extending between the peripheral portion and thesupport portion; and a fan assembly secured to the rear surface andprojecting toward the rear housing, the fan assembly including anelectrical motor and a fan blade rotatably coupled therewith, anelectrical switch operatively connected to the motor, and an actuatoroperatively coupled to the electrical switch and projecting outwardlyfrom the front surface. Mounting of the fan assembly on the centralsupport portion simplifies assembly and minimizes external size of theblower.

According to features of the invention, the rear housing further definesa chamber, a substantially circular access opening thereto, the fanassembly projects through the access opening into the chamber, theperipheral portion includes a substantially circular rim engaging theaccess opening which is covered by the front housing. This arrangementfurther optimizes the external configuration of the blower.

According to another feature of the invention, the grillwork portioncomprises a plurality of curved vanes extending between the rim and thecentral support portion. The curved vanes enhance the selection of adesired air discharge pattern.

According to other features of the invention, the front housing and therear housing are integrally molded units. These features reduce cost andfurther simplify assembly of the blower.

According to another feature, the invention includes a power cordconnected to the electrical switch and the front housing means furtherdefines a channel opening toward the chamber and retaining a portion ofa power cord connected to the switch. The channel provides aconveniently located protective housing for the power cord.

According to yet other features, the blower further comprises a baseincluding a downwardly projecting handle and adapted to support theblower on a support surface. Combining a base and downwardly projectinghandle enhances the compact external configuration of the blower.

According to other features of the invention, the base comprises onlythree legs, one of the legs is disposed in a plane bisecting the othertwo legs, a cross member extending between the other two legs forms thehandle, and the blower includes an orientation adjustment mechanism forthe one leg. The adjustment mechanism permits selective changes in theorientation of the blower to establish desired air discharge patterns.

According to further features of the invention, the adjustment mechanismis operable to change the length of the one leg, and the spacing betweenthe one leg and the other two legs. This arrangement facilitates theselective orientation of the blower.

According to additional features of the invention, the one leg comprisesa pair of spaced apart brackets retaining a pivot pin, and theadjustment mechanism comprises a rotary member disposed between thebrackets, having an eccentric hole rotatably coupled to the pivot pinand adapted to engage the support surface, and defining rotationlimiting stop surfaces for engaging the brackets to limit rotation ofthe rotary member on the pivot pin. Selective orientation of the bloweris provided by rotation of the rotary member between the limitsestablished by the stop surfaces.

DESCRIPTION OF THE DRAWINGS

These and other objects and features of the invention will become moreapparent upon a perusal of the following description taken inconjunction with the accompanying drawings wherein:

FIG. 1 is a perspective view of a portable fan according to theinvention;

FIG. 2 is a front view of the fan shown in FIG. 1;

FIG. 3 is an exploded view, partially in section of the portable fanshown in FIGS. 1 and 2; and

FIG. 4 is a partial cross-sectional view showing an adjustable leg onthe fan shown in FIGS. 1-3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

An air blower 11 according to the present invention includes a fronthousing 12, a rear housing 13 and base 14. The rear housing 13 defines achamber 16 and a plurality of rearwardly facing first air passage in theform of inlet openings 17. Also defined by the rear housing 13 is acircular opening 18 providing access to the chamber 16.

The base 14 includes a pair of front legs 21, 22 projecting downwardlyfrom a front portion of the rear housing 13 and a rear leg 23 projectingdownwardly from a rear portion thereof. Extending between the front legs21, 22 is a cross member 25 that is spaced from the front housing 12 andthe rear housing 13 so as to form a handle for the blower 11. The rearleg 23 is spaced rearwardly from the front legs 21, 22 and disposed in abisecting plane therebetween. Thus, the front legs 21, 22 and the rearleg 23 form a tri-pod for supporting the blower 11 on a suitable supportsurface (not shown). Preferably, the rear housing 13 and the base 14 areformed as an integrally molded unit.

The front housing 12 includes an annular peripheral rim portion 27,conforming to the circular access opening 18 in the rear housing 13, acentrally located central support portion 28 and a grillwork portion 29extending therebetween and defining a plurality of second air passagesextending between the annular or peripheral portion 27 and the centralportion 28. Forming the grillwork portion 29 are a plurality of curvedvanes 31 having opposite ends attached, respectively, to the rim portion27 and the central support portion 28. More particularly, the vanes eachincludes a first end connected to the central support portion and asecond end connected to the annular peripheral portion. The vanes areconnected between the central support portion and the peripheral portionindependently of each other. As clearly shown in FIG. 2, the vanes areall curved in the same direction and equally spaced from each other,with the spacing at the first ends being smaller than the spacing at thesecond ends. As also seen from FIG. 2, the central portion is circularin shape. In addition, the first ends of the vanes are connected atcircumferentially spaced points around the central portion whereby thesecond end of any vane is connected to the peripheral portionapproximately at the location of the intersection of a line drawntangent to the central portion at the point where the first end of thatvane is connected to the central portion.

As shown in FIGS. 1 and 3, the vanes each have a rectangularcross-sectional shape defining opposite flat surfaces facing toward theperipheral and support portions of the front housing. The flat portionsof the vanes are connected together by opposite edges of the vanes. Asshown in FIGS. 1 and 2, the width of the edges is less than the width ofthe flat surfaces of the vanes. Also, the vanes are completely disposedin a flat plane extending substantially perpendicular to the axis ofrotation of the fan. A plurality of internally threaded studs 32 projectrearwardly from a trough 33 formed by the rim portion 27 as shown inFIG. 3. Also formed by the front housing 12 are a front wall 34 and sidewalls 35 that extend between the central support portion 28 and thetrough 33 so as to form a rearwardly opening channel 40. The centralsupport portion 28 includes a rear surface 36 facing the rear housing 13and an oppositely directed front surface 37. Formed by the front surface37 is a circular cavity 38. A plurality of internally threaded studs 39extend rearwardly from the rear surface 36. Preferably, the fronthousing 12 also is formed as an integrally molded unit.

A fan assembly 41 (FIG. 3) is supported by the central support portion28 of the front housing 12. Included in the fan assembly 41 is anactuator knob 42, a conventional electrical rotary switch 43, anelectrical motor 44, a tranformer 45 and a fan blade 46. The transformer45 is attached to the electrical motor 44 and that unit is secured byscrews 48 to the rearwardly projecting studs 39 on the central supportportion 28. A drive shaft 51 rotatably couples the motor 44 to the fanblade 46 which projects into the chamber 16 formed by the rear housing13. Securing the rear housing 13 to the front housing 12 are a pluralityof screws 52 which engage the internally threaded studs 32. With thismounting of the fan, the curved vanes will inherently absorb torquecreated by the fan as it is rotated about the axis of the shaft 51.

The electrical switch 43 is retained within the cavity 38 in the centralsupport portion 28 and defines therewith an annular recess 53.Projecting forwardly from the electrical switch 43 is an actuator shaft54. Keyed for rotation with the actuator shaft 54 is the actuator knob42 which projects forwardly from the central support portion 28 of thefront housing 12. A rearwardly extending circular flange portion 56 ofthe actuator knob 42 is received by the annular recess 53 formed betweenthe central support portion 28 and the electrical switch 43. Connectedto the electrical switch 43 and extending through the channel 40 is apower cord 57. A plurality of electrical wires 58 connect the electricalswitch 43 to the motor 44 and the transformer 45.

The rear leg 23 is formed by a pair of spaced apart brackets 61, 62 thatproject downwardly from the rear portion of the rear housing 13.Extending between the brackets 61, 62 is an elliptically shaped pivotpin 63. Retained by the pivot pin 63 between the brackets 61, 62 is arotatable, circular disk member 66. As shown in FIG. 4, the disk member66 defines an eccentric hole 67 that accommodates the pivot pin 63.Projecting transversely from opposite sides of the disk member are afirst pair of ridges 71. Also projecting transversely from oppositesides of the disk member 66 and intercepting the first ridges 71 are asecond pair of ridges 72. Rotation of the disk member 66 on the pivotpin 63 in one sense is limited by engagement between the stop surfacesformed by the first ridges 71 and first stop surfaces formed by bottomedges 75 of the brackets 61, 62. Similarly, rotation of the disk member66 in the opposite sense is limited by engagement between the stopsurfaces formed by the second ridges 72 and second stop surfaces formedby the forwardly facing edges 76 of the brackets 61, 62.

OPERATION

During use, the air blower 11 is easily transported to a location inwhich air circulation is desired. Transportation is accomplished bymerely gripping the cross member handle 25 and moving the air blower 11to the desired location. Once a suitable position is attained, thereadily accessible actuator knob 42 can be rotated to actuate the switch43 and energize the electrical motor 44, thereby producing rotation ofthe fan blade 46. That rotation draws air inwardly through the inletopenings 17 in the rear housing 13 for discharge through the grillwork29 in the front housing 12. As air is discharged through the grillwork29, aerodynamic flow is enhanced by the conical shape of the actuatorknob 42 with its outwardly facing apex.

When in an established position, vertical orientation of air flowproduced by the blower 11 can be adjusted easily by rotation of the diskmember 66 on the pivot pin 63. As the disk member 66 is rotated on thepin 63 between the position shown by solid lines in FIG. 4 with thefirst ridges 71 engaging the bottom edges 75 of the brackets 61, 62 tothe position shown by dashed lines with the second ridges 72 engagingthe front edges 76 of the brackets 61, 62; the effective length of therear leg 23 is changed by a distance h and the spacing thereof from thefront legs 21, 22 is changed by a distance 1. Consequently, the tilt ofthe air blower 11 is changed and the orientation of air flow producedthereby is altered accordingly. Frictional engagement between theeccentric hole 67 in the disk member 66 and the pivot pin 63 will retainthe disk member 66 in any desired angular position between thoseillustrated in FIG. 4 to thereby establish any of a variety of desiredorientations for the blower 11.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is to be understood,therefore, that the invention can be practiced otherwise than asspecifically described.

What is claimed is:
 1. An air blower comprising:a) first housing meansdefining a plurality of first air passages; b) second housing meanssecured to said first housing means and having a central portion, anannular portion disposed radially outwardly of said central portion, anda grillwork portion forming second air passages extending between saidannular portion and said central portion, wherein said first airpassages and said second air passages are aligned axially; c) a fanassembly secured to said central portion, said fan assembly comprisingan electrical motor and a fan blade rotatably coupled therewith forrotation about an axis; d) said grillwork portion comprising a pluralityof vanes, each of which has a curved shape for absorbing torque createdby rotation of said fan, said curved shape extending between oppositefirst and second ends of the vane; and e) said vanes being connectedbetween said central portion and said annular portion with said firstend of each vane being connected to said central portion and said secondend of each vane being connected to said annular portion.
 2. An airblower comprising:a) first housing means defining a plurality of firstair passages; b) second housing means secured to said first housingmeans and having an annular peripheral portion, a central supportportion within said peripheral portion, and a grillwork portion formingsecond air passages extending between said peripheral portion and saidcentral support portion, wherein said first air passages and said secondair passages are aligned axially; c) a fan assembly secured to saidcentral support portion, said fan assembly comprising an electricalmotor and a fan blade rotatably coupled therewith for rotation about anaxis; d) said grillwork portion comprising a plurality of vanes, each ofwhich has a curved shape for absorbing torque created by rotation ofsaid fan, said curved shape extending between opposite first and secondends of the vane; and e) said vanes being connected between said centralsupport portion and said annular peripheral portion with said first endof each vane being connected to said central support portion and saidsecond end of each vane being connected to said annular peripheralportion.
 3. An air blower according to claim 2 wherein:a) said firsthousing means is a rear housing means; b) said first air passages areair inlet openings; c) said second housing means is a front housingmeans; d) said second air passages are air discharge openings; and e)said fan assembly is secured to said central support portion andprojects toward said rear housing means.
 4. An air blower according toclaim 3 wherein:said vanes are all arcuately curved in the samedirection.
 5. An air blower according to claim 4 wherein:said vanes areequally spaced from each other with the spacing at the first ends beingsmaller than the spacing at the second ends.
 6. An air blower accordingto claim 4 wherein:a) said central portion is circular in shape and thefirst ends of said vanes are connected at circumferentially spacedpoints around said central portion; and b) any vane with its first endconnected to a point on the central support portion has its second endconnected to said annular peripheral portion approximately at thelocation of the intersection of a line drawn tangent to said centralsupport portion at said point.
 7. An air blower according to claim 6wherein:a) each of the vanes has a rectangular cross-sectional shapedefining opposite flat surfaces of a predetermined width connectedtogether by opposite edges of a width which is less than saidpredetermined width; and b) said vanes extend between said annularperipheral portion and said central support portion with said oppositeflat surfaces facing toward said annular peripheral and central supportportions.
 8. An air blower according to claim 6 wherein:the vanes ofsaid grillwork are completely disposed in a flat plane extendingsubstantially perpendicular to the axis of rotation of said fan.
 9. Anair blower according to any one of claims 3-8 wherein:said front housingmeans is an integrally molded unit.
 10. An air blower according to claim3 wherein:said fan assembly further includes an electrical switchoperatively connected to said motor, and an actuator operatively mountedon the central support portion of said front housing means and coupledto said electrical switch, said actuator projecting outwardly of thefront housing means in a direction away from said rear housing means.11. An air blower according to claim 10 wherein:said actuator is aconically shaped knob having an apex projecting outwardly of the fronthousing means in a direction away for said rear housing means.